The present invention relates to a ramp bridging device (a transfer bridge or dock leveler), and has a bridge plate, the back end of which is pivotably mounted to the ramp or dock about a horizontal transverse shaft, and an extension which is located on the free end of the bridge plate, can be moved in the longitudinal direction of the bridge, and can be extended and retracted. The extension serves for rest and support on a platform which is to be loaded or unloaded. Below a continuous cover plate, the bridge plate is provided with longitudinal members which are parallel to one another. The edges of the bridge plate are preferably provided with vertical side plates. Furthermore, the extension is provided with a portion which extends approximately over the width of the bridge, and is intended for support on the platform. The extension is also provided with longitudinal members which are parallel to one another.
With the heretofore known ramp bridging devices of this general type, the cover plate of the extension extends far below the bridge plate or the cover plate thereof. In this connection, the cover plate of the extension is slotted; the longitudinal members of the bridge plate extend into these longitudinal slots so that they can also be effective in the front part of the bridge plate. However, this slotted construction has the drawback that the manufacture of the extension is made more difficult; furthermore, special support members must be provided on the longitudinal members of the bridge plate in order to assure the required rigidity for the bridge.
It is an object of the present invention to provide a ramp bridging device which overcomes these drawbacks.